Characterization of otitis media with effusion based on the ratio of albumin and immunoglobulin G concentrations in the effusion.

Objective: To characterize the groups of middle ear effusions (MEE) defined on the basis of the ratio of albumin and immunoglobulin G concentrations (A/G) in the effusion and to identify the correlation between these groups of MEE and the clinical features of otitis media with effusion (OME).

Study Design: A laboratory analysis of 88 samples of MEE and a retrospective analysis of the medical history of all patients was performed.

Setting: Tertiary referral center.

Patients: Thirty-three girls and 23 boys with OME were included in the study.

Intervention: The concentrations of albumin, immunoglobulins (IgG, IgA, and IgM), complement factors (C3, C4), and C-reactive protein were determined by means of nephelometry. Enzyme-linked immunosorbent assay was used to measure cytokines interferon-gamma, tumor necrosis factor alpha, interleukin (IL)-4, and IL-10 concentrations. Groups were defined according to A/G ratio in the effusions. Thirty-five children underwent allergy testing.

Main Outcome Measure: Two groups of MEE could be recognized on the basis of A/G ratio; the ratio was lower than 0.7 in group A and was higher than 0.7 in group B.

Results: Increased levels of interferon-gamma and tumor necrosis factor alpha were observed in group A, whereas IL-4 and IL-10 were dominating in group B. No association was found between the MEE groups and the clinical features of the disease or the atopic status of the patient.

Conclusion: These results suggest that various groups of OME can be categorized according to the differences in A/G ratio in the effusions. These differences can reflect the variances in the pathomechanism of the development of the effusion, the stage of the disease, or the clinical background of the patients.